The present invention relates to an orally operable, portable, water filtration device.
With each passing day, man-made chemicals and contaminants are introduced into our water supply. Many of these pollutants are unhealthful to drink and/or adversely affect the taste of water. Typically, travelers, hunters, and the like who wish to filter their water use some sort of orally operable, portable, water filtration device, such as a water filtration straw, which removes the pollutants from the water as it is sucked through the straw to the user's mouth. One type of water filtration straw comprises a hollow elongated tube. A porous material, such as felt or foam is inserted into the bottom end of the tube and is held in place by a screen mounted on the bottom end of the tube. Additional foam or felt is inserted into the top end of the tube and is held in place by a second screen mounted thereover. Filter material, such as granulated activated carbon, is disposed within the tube between the foam and/or felt materials.
In U.S. Pat. No. 4,767,544 to Hamblin, an orally operable water filter is described. The water filter includes an outer covering formed of a flexible, water impervious material and which defines an elongate enclosure. A flexible microporous filter membrane, having a pore size of not more than one micron, is disposed within the elongate enclosure and divides the enclosure into respective fluid inlet and fluid outlet compartments, such that the outlet may be placed in the mouth of the user and fluid inlet may be contacted with a source of water to be filtered by drawing the water through the filter using oral suction. Furthermore, the filter includes a flexible separator, disposed at least in the outlet compartment, for preventing the blocking of fluid over the surface of the filter membrane.
In U.S. Pat. No. 4,298,475 to Gartner, a portable water purifier is described. The water purifier comprises an elongated tube having a diameter of a size as to allow suction to be applied by a user's mouth, the tube having an interior conduit connecting an upper outlet and a lower inlet, the conduit having successive adjacent sections from the inlet and the outlet, a first section containing a primary filter material for removing particulate matter, a second section containing an iodinated cation ion exchange resin for removing harmful bacteria, viruses, and the like, a third section containing a secondary filtration material for removing additional particulate material, a fourth section containing activated carbon granules for removing undesirable odors, tastes and hydrocarbons, and a fifth section containing a secondary filter material for removing substantially all remaining particulate matter, whereby on the application of suction when the lower inlet is inserted into a source of contaminated water, the contaminated water is treated to permit the ingestion of water directed from the upper outlet.
In U.S. Pat. No. 1,333,011 to Crady, an individual filter is described. The individual filter comprises a pair of detachable sections telescopically arranged, one of which is provided with a mouth piece, each of the sections being provided at their outer ends with permanently attached screens, while their opposed or inner ends are provided with removable screens, the sections having the space between the screens filled with a filtering element preferably in the form of charcoal. The removable screens are each composed of a ring with a fine wire mesh secured to one edge thereof and a loop also secured to the rings for the purpose of providing for the convenient removal of the screens, the screens being held in position within the tubular members by screws or other fastening devices passing through the members and engaging the rings.
In U.S. Pat. No. 1,000,332 to Dyer, a pocket filter is described. The pocket filter comprises a tubular body, end foraminous cap members carried thereon, filtering material interposed between the cap members, a telescopic member secured to the tubular body and adapted to prevent displacement of one of the caps, one section of the telescopic member being provided with a slot adjacent to one terminal thereof, and a foraminous member adapted to be received by the slot, the member being prevented from displacement by the tubular body as set forth.
Other patents of interest include U.S. Pat. Nos. 4,894,154, 4,769,143, 4,578,187, 4,505,310, 4,369,512, and 4,309,992.